1. Field of the Invention
This invention relates generally to devices and methods for rinsing nasal passages and more specifically to devices and methods for providing a pressurized flow of a saline solution into and through a nasal passage.
2. State of the Prior Art
The paranasal sinuses are a group of four paired air-filled spaces that surround the nasal cavity and are located above and between the eyes and behind the ethmoid sinuses. The maxillary, frontal, ethmoid and sphenoid sinuses are named for the facial bones in which they are located. The maxillary sinuses, also called the maxillary antrechea and the largest of the paranasal sinuses, are located under the eyes in the maxillary bones of the face. The frontal sinuses are located superior to the eyes in the frontal bone, which forms the hard part of the forehead. The ethmoid sinuses are formed from several discrete air cells within the ethmoid bone between the nose and eyes. The sphenoid sinuses are located in the sphenoid bone at the center of the skull base under the pituitary gland.
The paranasal air sinuses are lined with respiratory epithelium and are joined to the nasal cavity by small orifices called ostia. The nasal passage runs from the nostrils to the pharynx. The ostia become blocked easily by allergic inflammation, or by swelling in the nasal lining that occurs with a cold. When this occurs, normal draining of mucus within the sinuses is disrupted, and sinusitis may occur. Rhinitis is another condition resulting from inflammation of the mucosa of a nasal passage.
Both sinusitis and rhinitis can result from exposure to viruses, bacteria, fungi or allergens, as well as exposure to smoke cold viruses, allergies to various allergens, smoke or other air pollutants or contaminants. When rhinitis occurs, common symptoms include stuffy nose, runny nose and post-nasal drip. The most common kind of rhinitis is allergenic rhinitis, which is usually triggered by airborne allergens such as pollen and dander. Allergic rhinitis may cause additional symptoms, such as sneezing and nasal itching, coughing, headache, fatigue, malaise and cognitive impairment. The allergens may also affect the eyes, causing watery, reddened or itchy eyes and puffiness around the eyes. When sinusitis occurs, whether acute or chronic, symptoms may include headache/facial pain or pressure of a dull, constant, or aching sort over the affected sinuses. This pain is typically localized to the involved sinus and may worsen when the affected person bends over or when lying down. Pain often starts on one side of the head and progresses to both sides. Acute and chronic sinusitis may be accompanied by thick nasal discharge that is usually green in color and may contain pus and/or blood. Often a localized headache or toothache is present. Infection of the eye socket is possible, which may result in the loss of sight and is accompanied by fever and severe illness.
These conditions are often treated with drugs such as decongestants that cause vasoconstriction in the sinuses. The goal most treatment is to prevent or reduce the symptoms caused by the inflammation of affected tissues. Intranasal corticosteroids are also used for conditions caused by allergens. Other measures that are often used include antihistamines, cromolyn and leukotriene receptor antagonists. Nonpharmacologic therapies, such as Nasal irrigation is another technique used to rinse the sinuses in order to remove mucus, allergens and contaminants from the sinus and nasal cavities.
Nasal rinsing or lavage often uses a saline solution dispensed into the nasal passage to cleanse and wash away mucus and allergy creating particles and irritants. Such nasal rinsing allows the sinuses to drain normally and often reduces the inflammation of the mucus membrane. One such apparatus and method for nasal rinsing is disclosed in U.S. Pat. No. 6,520,384 issued on Feb. 18, 2003, to Mehta, the entirety of which is incorporated by this reference. FIG. 1 is an illustration of the device set forth in the '384 patent, which includes a container 1 having flexible sidewalls 2 and a removable cap 3. The cap 3 has a rounded convex upper portion 4 curving away from an opening at the cap's uppermost surface and has a conduit 5 in the cap's interior. The conduit 5 extends into the container 1 when the device is fully assembled. The sidewalls 2 of the container, filled with a saline solution, are compressed to urge the saline solution through the conduit 5 and through the opening 6 in the cap and into a nasal passage, the cap 3 being pressed against a nostril.
The devices illustrated in FIG. 1 has several limitations, however, including a limitation of the amount of saline solution that can be forced from the container with each squeeze of the container. Moreover, because the device requires a squeezing of the sidewalls to expel the saline solution, it is difficult to control the pressure and thus the flow rate of solution being expelled from the device in order to provide a steady flow of solution into a nasal cavity. Moreover, the device necessarily provides saline solution in quick bursts and therefore does not provide continuous flow of solution over any extended period of time to provide continuous flushing or rinsing of the nasal passage. Furthermore, the size of the container to be hand held necessarily limits the amount of saline solution that can be provided in each container and therefore often requires multiple preparations to be made for each rinsing operation. Because of these limitations, it is often the case that during use a significant amount of saline solution is wasted. Moreover, the configuration of the device can result in contaminated material being drawn into the container during use.
Thus, there is a need in the art to provide a more effective device for nasal rinsing that allows a user to control the rate of flow of solution from the device over a period of time, that can provide a large volume of solution into a nasal cavity in a short period of time, that allows the user to control the flow rate of the solution into the nasal passage and that prevents contaminated solution from reentering the container.